What are “shin splints”?
Did you know that 10-20% of all leg pain in runners is due to an injury called “shin splints”? (1) Shin splints is really an umbrella term that relates to shin pain that largely occurs in runners or sports that heavily involve running. Typically, pain will originate from the lower third to two thirds of the inside of your shin. Often it is extremely tender to touch if you press along the inside edge of the shin bone (tibia).
As I say, “shin splints” itself is basically a way of saying that your shin hurts. There are more specific pathologies that form this construct of shin splints. These being:
• Medial Tibial Stress Syndrome (MTSS)
• Stress reactions and stress fractures
• Chronic exertional compartment syndrome
Medial Tibial Stress Syndrome
By far the most common cause of shin pain is MTSS. Essentially this is an overuse and an overload type of injury. Muscles and fascia (connective tissue) attach into the inside portion of the tibia (shin bone). Under excessive loading (i.e. running/landing/jumping/changing directions/training on harder surfaces) this soft tissue can pull on the attachment site along the tibia and cause irritation and inflammation to the periosteum (bone). This results in pain, sometimes visible swelling and interference with sport participation.
Stress reactions and stress fractures
When you exercise you place strain on all tissue in the body including bones. Appropriate levels of loading are good because you can actually improve bone health and strength through engaging in impact exercise. The problem comes if you are overworking a structure through excessive volume, frequency and intensity of loading. Over time this causes the breakdown of bone to occur at a greater rate than bone repair occurs at. This can result in a stress fracture. Characterised by very specific sharp pain directly on the bone, it’s important to spot these early to prevent significant issues further down the line.
Chronic Exertional Compartment Syndrome
Chronic exertional compartment syndrome (CECS) is estimated to account for around 27%(2) of cases in persistent leg pain scenarios. Which sounds alarmingly high but the important bit to note is that it is in PERSISTENT cases, not ALL leg pain. The mechanism by which pain is generated is unclear but is thought to be due to increased pressure developing within confined spaces of the calf. Muscle volume can increase up to 20% during exercise, and so a common trait is that someone will develop pain at pretty much the same point into a run.
Typically, a burning sensation develops around 15 minutes into a run and then disappears within 30 minutes of rest. This is trickier to treat and whilst conservative measures may be of value, surgery is sometimes needed to reduce the pressure building within in the calf in response to exercise.(3) If you have had shin splint type symptoms that haven’t changed with rest or intervention it is worth seeking the advice of a health professional to investigate the issue further.
As alluded to above, shin splints are largely caused by inappropriate loading over a short(ish) time frame. A change in load occurs in multiple ways:
- You start a new sport or activity that’s high impact or involves lots of running
- You increase the amount you’re training at a higher rate than your body can adapt to in that time frame
- You start training on a hard(er) surface(s)
- General and specific muscle weakness of the leg
- Change in footwear
- Weight or stature increase
- Training whilst fatigued
Any or a combination of these factors can cause the onset of shin splints. To read more about how to calculate how much load you’re placing on your body in training cycles read my blog on avoiding injuries in the new year by clicking here.
Furthermore, a recent study(4) reviewing literature pertinent to MTSS suggests that there are certain risk factors for developing the condition which include; female sex, increased weight, higher navicular drop (the inside arch of your foot is closer to the floor), previous running injury, and greater outward rotation of the hip with the hip in flexed (bent) position when running.
5 Tips to beat shin splints
1) Take stock of your starting fitness levels. You can do quick screenings of yourself prior to starting a new exercise or if you are planning on dramatically increasing the frequency that you exercise. Two simple tests are; can you perform a single leg squat of reasonable depth without needing to grab on to the wall or with your knee deviating towards the other side. And how many heel raises can you do? One study(5) documents the number of heel raises achieved in a healthy population of people of a variety of ages as:
How do you match up?
If the answer to these questions is, “I’d rather keep that private thank you very much, don’t be so nosey!” then I suggest planning carefully how you intend to go about your endeavours. This brings us nicely to tip number 2….
- Include strength work as part of your training schedule. Building muscle strength of the calf, hamstrings, quadriceps, gluteals and core muscles will help you maintain more efficient and controlled movement in running, sprinting and changing direction. It also pays dividends to build endurance of the muscles too, especially if you are a distance runner who needs to be strong for a prolonged period. Often good programmes can be found online or on YouTube. For tailored advice see a clinician who can help you design one to combat deficits you may have.
- Alter the surface you’re training on. Varying the surface you run on helps to train the body on a variety of terrains which is great news for adaptability. Without meaning to add fuel to fire of “pounding the pavement is bad for you” (it isn’t, there are studies that support this and everything!), in the context of shin splints harder surfaces generates more ground reaction forces. Spending some time training off road provides softer surfaces and forces you to make subtle changes in how you run and that variety means avoiding repeatedly loading the tissue in the same way.
- Don’t train if you’re tired. Training after a bad nights sleep, an evening of fun and frolicking or simply a doozy of a week at work can lead to alterations in running technique and movement control. In the same way that being asked mentally taxing questions when sleep deprived or hungover is about as much fun as it sounds, asking your body to haul itself round on minimal energy reserves is never going to end well. Do this frequently and eventually your body will activate operation enforced rest.
- Remember your nutrients and vitamins. Depending on where you are living makes an enormous difference as to what your vitamin D levels are likely to be like. Vitamin D is essential for many wonderfully important body functions but included in that is bone health. Latitudes from 0° to around 35° north or south allow year-round vitamin D production. Latitudes above 50° north will experience Vitamin D winter -you can’t produce Vitamin D from sunlight – from around October until April (for reference London latitude 51°). Now, and I can’t stress this enough, YOU MUST SEEK GUIDANCE FROM A MEDICAL PROFESSIONAL before you start self-medicating vitamin D supplements because too high levels of Vitamin D will also be particularly unpleasant for you. If you’re in a zone that doesn’t get year-round vitamin D from the sun, spend all your time indoors or have a particularly poor diet then it might be needed, but you must have that chat with your physician first. The point here is to make sure you are eating a good balanced diet of vitamin and mineral rich fruit and vegetables in order to maintain vitamin D levels, amongst others, to facilitate good bone health.
Take home messages
- Shin splints is a common occurrence in runners
- It has multiple causes, all of which largely come down to excessive load on the bone
- You can remedy this by taking simple actions to vary your training, make sure you are fit for purpose and being aware of how all-round health and fatigue levels affect performance.
- Sievers M, University OW, editors. The Relationship of Lower Extremity Range of Motion and Incidence of Shin Splints in Collegiate Runners: A Pilot Study. Student Symposium; 2019 2019.
- Blackman PG. A review of chronic exertional compartment syndrome in the lower leg. Med Sci Sports Exerc. 2000;32(3 Suppl):S4-10.
- Tucker AK. Chronic exertional compartment syndrome of the leg. Curr Rev Musculoskelet Med. 32010. p. 32-7.
- Reinking MF, Austin TM, Richter RR, Krieger MM. Medial Tibial Stress Syndrome in Active Individuals: A Systematic Review and Meta-analysis of Risk Factors. Sports Health. 92017. p. 252-61.
- Monteiro DP, Britto RR, Fregonezi GF, Dias FAL, Silva M, Pereira DAG. Reference values for the bilateral heel-rise test. Braz J Phys Ther. 212017. p. 344-9.